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81.
In vitro improvement of quail primordial germ cell expansion through activation of TGF‐beta signaling pathway
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82.
Marzieh Taghipour Shamsollah Ayoubi Hossein Khademi 《Soil & Sediment Contamination》2011,20(8):921-937
Heavy metals’ origin, accumulation, and distribution in soil have been the focus of much attention by many researchers. The objective of this study was to recognize the sources of heavy metals in surface soils in Hamadan Province in western Iran using multivariate geostatistical techniques. A total of 263 surface (0–10 cm) soil samples and 18 rock samples from major parent materials were collected. Cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) contents of the samples were determined. Selected soil physical and chemical characteristics were also measured. A multivariate geostatistical analysis was performed to identify the common source of heavy metals. The quantities of Co, Cr, and Ni were found to be associated with parent rocks, corresponding to the first factor termed the “lithologic component.” The second factor was mainly attributed to Cu, which also comprised the first and third factors, indicating a mixed source both from lithologic and anthropogenic inputs. Zn and Pb contents were related to the anthropogenic activities and comprised the third factor. A significant correlation was found between metals from the lithogenic sources and selected soil properties such as soil organic matter, clay, CEC, and carbonate, indicating an interaction among them. Generally, Zn and Pb showed a less significant correlation with soil properties. 相似文献
83.
F Roman O Della Zuana M Lonchampt G Saint Romas J Duhault 《Comptes rendus des séances de la Société de biologie et de ses filiales》1984,178(4):372-381
Biogenic amines in pons and striatum have been dosed in twenty-four months old Wistar male rats. Choline acetyltransferase (CAT) and acetylcholine esterase (ACHesterase) activities, [3H] choline uptake by a synaptosomal preparation, [3H] quinuclidinyl benzylate (QNB) binding to muscarinic cholinergic receptors have been determined in hippocampus. Malondialdehyde (MDA) levels in plasma, in liver and in lungs and the characteristics of the skin collagen have been evaluated. Important differences are shown in comparison with three months old of the same strain animals. 相似文献
84.
Genetic Mapping in the Lignin-Degrading Basidiomycete Phanerochaete chrysosporium 总被引:1,自引:0,他引:1
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A method of meiotic segregation analysis based on recombinant selection in the homothallic basidiomycete Phanerochaete chrysosporium was developed. Using this method, we were able to reveal linkage relationships and to estimate recombination frequencies between seven mutations to auxotrophy. We detected two linkage groups, the first containing four and the second three of the seven mapped mutations. 相似文献
85.
Omid Haghighi Soheila Davaeifar Hossein Shahbani Zahiri Hadi Maleki Kambiz Akbari Noghabi 《International journal of peptide research and therapeutics》2020,26(2):783-793
Glutamate dehydrogenase (GDH), which is present in most bacteria and eukaryotes’ mitochondria, plays an important role in amino acid metabolism. In g 相似文献
86.
Novotnik Breda Nandy Arpita Venkatesan Senthil Velan Radović Jagoš R. Fuente Juan De la Nejadi Siavash Silva Renzo C. Kouris Angela Thangadurai Venkataraman Bryant Steven Karan Kunal Shor Roman Strous Marc Larter Stephen R. 《Reviews in Environmental Science and Biotechnology》2020,19(1):217-240
Reviews in Environmental Science and Bio/Technology - The world’s energy system is still dominated by fossil fuels. While there is a rapid reduction in the cost of renewable energy and the... 相似文献
87.
Effect of Drought Stress on Certain Morphological and Physiological Characteristics of a Resistant and a Sensitive Canola Cultivar 总被引:1,自引:0,他引:1
Ghorban Khodabin Zeinolabedin Tahmasebi‐Sarvestani Amir Hossein Shirani Rad Seyed Ali Mohammad Modarres‐Sanavy 《化学与生物多样性》2020,17(2)
Water stress is one of the main abiotic factors that reduces plant growth, mainly due to high evaporative demand and low water availability. In order to evaluate the effects of drought stress on certain morphological and physiological characteristics of two canola cultivars, we conducted a factorial experiment based on a completely randomized design. The findings show that drought stress exacerbations result in the plant's response to stress due to increased canola resistance caused by changes in plant pigments, proline, catalase, ascorbate peroxidase, peroxidase, superoxide dismutase and malondialdehyde, glucose, galactose, rhamnose and xylose. These in turn ultimately influence the morphological characteristics of canola. Drought stress reduces the concentration of carotenoids, chlorophyll a, chlorophyll b, total chlorophylls; however, glucose, galactose, rhamnose, xylose, proline, catalase, ascorbate peroxidase, peroxidase, superoxide dismutase, malondialdehyde (in leaves and roots) and the chlorophyll a and b ratios were increased. Reduction of plant height, stem height, root length, fresh and dry weight of canola treated with 300 g/l PEG compared to non‐treatment were 0.264, 0.236, 0.394, 0.183 and 0.395, respectively. From the two canola cultivars, the morphological characteristics of the NIMA increased compared to the Ks7 cultivar. Interaction effects of cultivar and drought stress showed that NIMA cultivar without treatment had the highest number of morphological characteristics such as carotenoid concentration, chlorophyll a, chlorophyll b, total chlorophylls a and b, whereas the cultivar with 300 g/l PEG (drought stress) had the highest amount of proline, malondialdehyde, soluble sugars and enzymes in leaves and roots. Increasing activity of oxidative enzymes and soluble sugars in canola under drought stress could be a sign of their relative tolerance to drought stress. 相似文献
88.
Foroughi Kobra Jahanbani Sarvin Nazarnezhad Simin Khastar Hossein Jafarisani Moslem Tashakori Mersedeh Kazemi Seyedeh Sareh 《International journal of peptide research and therapeutics》2020,26(2):1115-1126
International Journal of Peptide Research and Therapeutics - Survivin is a unique member of the inhibitor of apoptosis protein family. Research has approved Survivin’s ability to interact... 相似文献
89.
Nikkhil Velingkaar Volha Mezhnina Allan Poe Kuldeep Makwana Richa Tulsian Roman V. Kondratov 《Aging cell》2020,19(4)
Caloric restriction (CR) has positive effects on health and longevity. CR in mammals implements time‐restricted (TR) feeding, a short period of feeding followed by prolonged fasting. Periodic fasting, in the form of TR or mealtime, improves metabolism without reduction in caloric intake. In order to understand the relative contribution of reduced food intake and periodic fasting to the health benefits of CR, we compared physiological and metabolic changes induced by CR and TR (without reduced food intake) in mice. CR significantly reduced blood glucose and insulin around the clock, improved glucose tolerance, and increased insulin sensitivity (IS). TR reduced blood insulin and increased insulin sensitivity, but in contrast to CR, TR did not improve glucose homeostasis. Liver expression of circadian clock genes was affected by both diets while the mRNA expression of glucose metabolism genes was significantly induced by CR, and not by TR, which is in agreement with the minor effect of TR on glucose metabolism. Thus, periodic fasting contributes to some metabolic benefits of CR, but TR is metabolically different from CR. This difference might contribute to differential effects of CR and TR on longevity. 相似文献
90.
Pegah Rahimizadeh Tohid Rezaei Topraggaleh Mohammad Hossein Nasr‐Esfahani Niloofar Ziarati Shahab Mirshahvaladi Vahid Esmaeili Soroush Seifi Poopak Eftekhari‐Yazdi Abdolhossein Shahverdi 《Molecular reproduction and development》2020,87(1):115-123
Failed oocyte activation has been observed in unexplained infertile (UI) and asthenoteratozoospermic (AT) men. The deficiency of phospholipase C‐zeta (PLCζ) could be a possible reason for such failures and has not been studied yet. We investigated the expression and localization of PLCζ protein in the sperms of patients with UI and AT conditions. The relationships between PLCζ‐related parameters with male age, sperm characteristics, DNA integrity, and cellular maturity were assessed. Semen samples were collected from fertile (n = 40), UI (n = 40), and AT (n = 40) men. Subsequently, semen analysis, DNA fragmentation, hyaluronic acid‐binding ability, and PLCζ level along with its distribution were evaluated using computer‐assisted sperm analyzer, sperm chromatin structure assay (SCSA), hyaluronic acid‐binding assay (HBA), western blot analysis and immunofluorescence microscopy, respectively. Unlike SCSA, the values of HBA, and PLCζ expression were significantly reduced in UI and AT patients compared to fertile men, whereas no significant differences were observed among the experimental groups in terms of PLCζ localization patterns. The regression analysis also showed that HBA is the only variable associated with PLCζ levels. Furthermore, the correlation of male age with PLCζ localization in postacrosomal, equatorial, and acrosomal+postacrosomal+equatorial (A+PA+E) patterns, as well as the relation of normal morphology, with the (A+PA+E) pattern, remained in the regression model. Our findings indicated that reduced PLCζ level along with the increased DNA fragmentation and impaired maturation may be possible etiologies of decreased fertilization in the studied subjects. 相似文献